Effects of dexmedetomidine on immune response in patients undergoing radical and reconstructive surgery for oral cancer

Oral cancer is one of the most common malignancies in the world. The present study aimed to investigate the effects of dexmedetomidine on immune response in patients undergoing radical and reconstructive surgery for oral cancer. Patients were randomly divided into the dexmedetomidine and control groups. Within 15 min before anesthesia induction, dexmedetomidine was infused with a 0.5 µg·kg(−1) loading dose followed by a maintenance dose of 0.4 µg·kg(−1)·h(−1) to the end of operation in the dexmedetomidine group, whereas the same volume of saline was administered in the control group. Blood samples were obtained at five time-points: 30 min Before induction (T(0)), 1 h after induction (T(1)), end of the operation (T(2)) and 24 (T(3)) and 48 h (T(4)) after the operation. The T lymphocyte subsets (including CD3(+), CD4(+) and CD8(+) cells) and CD4(+)/CD8(+) ratio, B lymphocytes, dendritic cells and myeloid-derived suppressor cells (MDSCs) were analyzed by flow cytometry. All immunological indicators, except CD8(+) cells, significantly decreased between the two groups at T(1–3) compared with T(0) (P<0.05). The percentages of CD3(+), CD4(+), dendritic cells and the CD4(+)/CD8(+) ratios were significantly higher at T(2–4) and the percentages of MDSCs were significantly lower at T(2–4) in the dexmedetomidine group compared with the control group (all P<0.05). These findings suggested that dexmedetomidine can attenuate immunosuppression in patients undergoing radical and reconstructive surgery for oral cancer.